OCCUPATIONAL EXPOSURE AND LUNG-CANCER RISK IN A COASTAL AREA OF NORTHEASTERN ITALY

A case-control study of lung cancer and occupational exposure was cond ucted in a coastal area of Northeastern Italy where metallurgical and mechanical industries, docks and shipyards are located. Cases comprise d 756 men who died of primary lung cancer in a 5-year period. Controls comprised 756 male subjects dying from other causes during the same p eriod. Occupational exposures to lung carcinogens were assessed accord ing to a job title-based approach, using two separate lists of industr ies/occupations recognized as being causally associated (list A) or su spected of being causally associated (list B) with lung cancer in huma ns. Exposure to asbestos was classified as absent, possible, or defini te. After adjustment for cigarette smoking and place of residence, a s ignificant association was found between lung cancer and occupations i n both list A [relative risk (RR) = 2.25, 95% confidence interval (CI) = 1.68-3.03] and list B (RR = 1.33, 95% CI = 1.03-1.71). A significan t excess risk was found for workers with definite exposure to asbestos as compared to those with no exposure to lung carcinogens (RR = 1.98, 95% CI = 1.42-2.75). Among occupations with recognized exposure to lu ng carcinogens other than asbestos, a significant excess risk for lung cancer was observed in iron and metalware workers. In occupational gr oups with definite exposure to asbestos, elevated risk estimates were found for shipyard workers, dockworkers, carpenters, and electricians. The combined effect of smoking and asbestos was found to be compatibl e with that expected under a multiplicative model. The overall populat ion-attributable risk (ARp) for cigarette smoking was found to be 87.5 %. The ARp estimate for occupations in list A was 16.0%. The estimate increased to 25.3% (95% CI = 16.2-34.4) when occupations in list B wer e included. The ARp estimate for possible or definite exposure to asbe stos was 20.0% (95% CI = 11.5-28.5). With regard to the histologic typ es of lung cancer, significant associations were found between definit e exposure to asbestos and squamous cell carcinoma (RR = 2.00, 95% CI = 1.28-3.11), small cell carcinoma (RR = 2.11, 95% CI = 1.31-3.39), an d adenocarcinoma (RR = 2.16, 95% CI = 1.32-3.53).